UPDATE 2.22PM: State Highway 23 is reopen with a reduced speed of 30km/h after a serious crash earlier today.

A police spokesperson says the speed restriction will be in place "while an oil spill is cleared".

"Motorists are advised to expect delays in the area and drive with caution," says the police spokesperson.

"Police thank motorists for their patience."

EARLIER 9.48AM: One person has died following a serious crash in Raglan earlier today.

Two other people are being transported to hospital with minor injuries, says a police spokesperson.

"The road is closed and diversions are in place at SH23 and Okete Road.

"We continue to ask motorists to please avoid the area."

EARLIER:

Emergency services are responding to a serious crash in Raglan.

Police were notified of the two-vehicle crash along SH 23 at "around 8:15am".

"Traffic management is being put in place," says a police spokesperson.

According to Google Maps, traffic is moving slowly following the incident.

Image: Google Maps.

"Motorists are asked to please avoid the area."

SunLive is working on gathering more information and will provide an update as soon as possible.